Semiconductor devices have become progressively more complex, driven at least in part by the demand for enhanced processing speeds and smaller sizes. While the benefits of enhanced processing speeds and smaller sizes are apparent these characteristics of semiconductor devices also can create problems. In particular, higher clock speeds can involve more frequent transitions between signal levels, which, in turn, can lead to a higher level of electromagnetic emissions at higher frequencies or shorter wavelengths. Electromagnetic emissions can radiate from a source semiconductor device, and can be incident upon neighboring semiconductor devices. If the level of electromagnetic emissions at a neighboring semiconductor device is sufficiently high, these emissions can adversely affect the operation of that semiconductor device. This phenomenon is sometimes referred to as electromagnetic interference (“EMI”). Smaller sizes of semiconductor devices can exacerbate EMI by providing a higher density of those semiconductor devices within an overall electronic system, and, thus, a higher level of undesired electromagnetic emissions at a neighboring semiconductor device.
One way to reduce EMI is to shield a set of semiconductor devices within a semiconductor device package. In particular, shielding can be accomplished by including an electrically conductive casing or housing that is electrically grounded and is secured to an exterior of the package. When electromagnetic emissions from an interior of the package strike an inner surface of the casing, at least a portion of these emissions can be electrically shorted, thereby reducing the level of emissions that can pass through the casing and adversely affect neighboring semiconductor devices. Similarly, when electromagnetic emissions from a neighboring semiconductor device strike an outer surface of the casing, a similar electrical shorting can occur to reduce EMI of semiconductor devices within the package.
While an electrically conductive casing can reduce EMI, the use of the casing can suffer from a number of disadvantages. In particular, the casing is typically secured to an exterior of a semiconductor device package by an adhesive. Unfortunately, the casing can be prone to peeling or falling off, since binding characteristics of the adhesive can be adversely affected by temperature, humidity, and other environmental conditions. Also, when securing the casing to the package, the size and shape of the casing and the size and shape of the package should match within relatively small tolerance levels. This matching of sizes and shapes and associated precision in relative positioning of the casing and the package can render manufacturing operations costly and time consuming. Because of this matching of sizes and shapes, it also follows that semiconductor device packages of different sizes and shapes can require different casings, which can further increase manufacturing cost and time to accommodate the different packages.
It is against this background that a need arose to develop the semiconductor device packages and related methods described herein.